Feet for sanding machines



Nov. 27, 1928. 4 1,692,898

- E. E. HUMMERICH FEET FOR SANDING MACHINES Filed May 1, 1925 Patented Nov. 2 7, 1928.

' UNITED. STATES ELTON E. HUMMERICH,

PATENT OFFICE- OF DAYTON, OHIO, ASSIGNOB, BY MESNE ASSIGNMENTS, TO

THE NATIONAL CASH REGISTER COMPANY, OF DAYTON, OHIO, A CORPORATION OF MARYLAND.

FEET non sanmne MACHINES.

Application filed May. 1, 1925. Serial No. 27,198.

llhis invention relates to feet for use with pneumatic sanding machines, and more particularly to the adaptation of specific material to such usage.

The principal object of this invention is to provide feet for pneumatic rubbing machines which feet are resilient and which are of a material having sufficient adhesive properties to cause sand paper to adhere with enough tenacity to prevent relative movement between the feet and said paper. I

It is also an object of this invention to construct said feet in such a manner that the sandpaper can be easily detached-therefrom when it becomes worn.

Still another object is preventing distortion in to provide means .for the shape of said feet .Whenthey .are operating at high speed and the essential .under pressure.

With these and incidental objects in view, the invention includes certain novel features of construction and combinations of parts, elements of which are set forth in appendedclaims, and a preferred form or embodiment of which with reference to the drawings which accom-- panyandform part of this specification. Of saidfigures: i

. Fig.1 is a perspective view of the pneumatic rubbing machine with which the feet of the present, invention may be used. Fig. 2 is a detail perspective view of the fabric envelope which prevents distortion of the feet under pressure. i

r Fig. 3 is a detail perspective of the metal plate around which the feet are molded and which forms a convenient means of fastening said feet to the rubbing machine.

Fig. 4 is a detail side elevation of the feet in their position of movement in which they are closest together. This figure shows how the sand paper buckles up between the feet when they are in this position.

Fig. 5 is a section through one of the feet.

General description.

It has long been a problem in the sanding machine art to provide means which would hold the sand paper securely while the machine was in operation and at the same time permit the easy removal of the worn out sand paper. Applicant has devised a very simple but very eflicient means for solving the above mentioned problem. It consists of using a foot of substantial thickness made of a gelatinous material combined with glue, the exact formula for" which will be hereinafter disclosed. This material is melted and mixed with the glue. It is then poured into suitable molds to formthe feet which, when solidified, are attached by means to be later described to thedriving mechanism of a pneumatic rubbing machine. This machine is preferably of the type shown in the application of H. B. Scott, No. 564,774, filed May 31, 1922,

' but any suitable driving device can be used.

It is not intended to limit this invention to use with sand paper as it might be adapted for use in any rubbing, polishing or buffing operation.

Only a very brief description of the rubbing machine used in connection withthis invention will be given herein, as the specific construction thereof forms no part of the invention, and reference can be made to the co pending application above mentioned for a is hereinafter described i The rubbing machine to which the invenmore extended description.

tion" is shown applied, includes side walls 30 atop plate 32 which comprises ahand grip shaped to fit the hand of the operator.

The air or other fluid under pressure is ad-' mittedinto the device through an inlet port .33 under the control of an inlet valve operated by a manipulative element 34., by means of which the machine can be started or stopped. This manipulative element is adapted to be operated by the first fingerof the operator.

When the air is admitted to the machine, it serves tooperate two pistons which are thereby reciprocated towards and from each other 'in a single cylinder, neither of which are shown herein. Directly connected to said pistons are two members (Figs. 1 and 4:) which are, of course, reciprocated in opposite directions with said pistons.

' As above noted the feet best adapted for use with this machine must be first resilient and then adhesive. The following formulae are for a material from which these-feet may be made. The first formula given is for feet to be used in winter or cold climates; and the second formula is for feet to be used in sumdifferent proportions are necessary in differ- Formula [i 0. 1.

'Supercabinet glue pounds Gelatine 35 pounds Water pounds Glycerine 90 pounds I f Carbolic acid 31 ounces(8 5%solution) .Fomwla No. 2. Supercabinet glue 2%.pounds Gelatine 22?;pounds Water 37 pounds Glycerine j 18 pounds Carbolic acid 20 'ounces (85% solution) The materials given in the above-'formulae are commingled and melted until they form a fluid, and this fluid'is then poured into a suitable mold in which a metal reinforcing and bracing core or platev36 (Figs. 3 and 5) has been previously inserted. The mold (not shown has four holes formed in its bottom wall t rough which the four projections .37 of the core plate 36 extend. The distance which the projections 37 will extend through the openings in the mold is limited by shoulders formed about midway of said-projections. It can thus be seen that the core plate 36'will be supported from the, bottom of the mold'a distance equal to that between the shoulders 38 andthe plate. The core plate 36 has several holes drilled therein to facilitate access of the material tothe mold'on'both sides of theplate, and, when the fluid .mate-.

rial is poured into the mold, the core late will be imbedded in said material, as can e clearly seen from the sectional view shown in Fig. 5. Before the mold is filled, the metal plate is painted with asphaltum paint, or. any other suitable'substa'nce, which causes the com- -position, when it has hardened, .to i adhere v and adhesiveness may beusedh tightly'to the metal. Each of the projections 3.7 of the core plate 36 has a hole 39 drilled therein. These holes are tapped and the feet are adapted to be secured to the reciprocating members 35 by means of screws 40w ich enter the holes 39 and fasten the feet securely to, the moving members of the rubbing machine.

It is to be understood that applicant does not limit his'invention to the precise materials or quantities given in the above mentioned formulae, as any suitable material hav ing the requisite characteristics of resiliency Before the ,core late 36 is inserted in the mold, a fabric enve ope 41 (Figs. 2 and 4) is inserted therein. This envelope may be the size of the mold, or smaller, and has four 1 openings 42 therein, through which the projections 37 of the plate 36 may extend. "If the envelope is smaller than the mold, there will be a portion of thegelatinous material on the strengthen thesaid envelope. The envelope covers the top and all four sides of the foot, leavin "only the bottom or working face thereog uncovered. The function of the en- -mer or hot climates,it havingobeen found that outside of the envelope which serves velope, which is preferably madeof linen or 1 some other suitable fabric, is to prevent any spreading of the material of which the foot.

is compbsed, due'to the weight of the machine or the pressure put thereon by the operator. It is also useful to counter-act the distorting effects of'the'sudden changes of-direction of thefeet at theends of the piston stroke and the disintegration of the material when the machine is running at high speed. Another purpose of the envelope is to prevent the cutting of the gelatinous material if the foot should come into contact vwitlithe work orother objects during its operation.

' Operation. h I

feet made in accordance with the present invention, 1t necessary to dampen the feetto give them the proper adhesive, qualities. This is done b placing the device .on a damp'felt pad an operating it fora short time. This will not only dampen the feetbut the heat will also help tom The machine is then placed on the back of a piece of sand paper which is cut to the right size. The paper will adhere'to the feet with suflicient force to prevent slippage and the operation may be commenced. v v The machine is always laced on the paper with the feet at their fart est position apart.

Then :du'rin" the operation when the feet jects'primarily stated, it is to be understood" that it is not intended to confine the invention to the one form or embodiment herein disclosed, for it is s Sceptibl'e of embodiment 1 in various forms all coming .of the claims which follow.

What is claimed is: f

- 1. Asandingmachinehaving reciprocating members, feet formed of an adhesive gelatmove .towar s each other, ,the paper willbuckle' in the'middle and move upwardin a,

1, 105" becomes worn,the machine within the scope I ggne'rated by the friction i a e the feet more adhesive.

inous material of substantial thickness fastenedto said members, and a fabric envelope adapted to cover all but the workin'g'faces of saidfeet. Y

' formed of a gelatinous and elastic working foot composed masses tial thickness, and secured to said member for the purpose set forth.

3. In a machine of the class described, a movable member carried thereby, and a foot adhesive material of substantial thickness, and secured to said member for the purpose set forth.

4. In a machine of the class described, a working foot composed of an adhesive and gelatinous material of substantial thickness, and a reinforcing means embedded in said material.

5. In a machine of the class described, an of an adhesive {gelatinous material of substantial thickness,

- working working block of elastic,

and a reinforcing means extending in parallelism with the surfaces of the foot.

6. In a machine of the class described, a working foot of resilient adhesive material of substantial thickness, and reinforcing and restraining means extending along the sides of the sides of said foot.

7 In a machine of the class described, a working foot of elastic, adhesive material, of substantial thickness, and a one piece reinforcing means extending around and on thetop of the foot. v

8. In a machine of the class described, a working foot comprising an attaching element, a coat of paint on said element, and a inherently adhesive material of substantial thickness molded about said painted element. l i 9. In a machine of the class described, a

foot comprising an attaching element, a coat of paint on said element, and a block of adhesive materiaf of substantial thicknessmolded about said painted element.

10. In a machine of theclass described, a

foot comprising an attaching, element, and a block of inherently adhesive, gelatinous material of substantial thickness molded about said element.

11. In a machine of the class described, a working foot comprising an attaching element, and a block of elastic, gelatinous and adhesive material of substantial thickness molded about said element.

ment, and a block of elastic, inherently adhesive material of substantial thickness molded about said element. i

13. In a machine of the class described, the combination with a reciprocating member; 0 a foot formed of an elastic, gelatinous material of substantial thickness inherently adhesive to present a sticky surface to which rubbing material adheres,and connected to the reciprocating member.

14. In a machine of theclass described the combination with a reciprocating member of a foot connected thereto, and formed ofa gelatinous material of substantial thickness, inherently adhesive to present a sticky surface to which rubbing material adheres; and a bottomless fabric envelope applied to the foot to reinforce and material of the foot against disintegration.

15; A foot for abrading, bufling and polishing machines or the like, formed of an inherently adhesive, gelatinous material of substantial thickness, to present a sticky surface to rubbing material, and adapted to retain its consistency under heat created by friction at high speeds. v

16. A foot for abrading, bufling and polishing machines or the like, formed of a block of elastic, inherently adhesive material of substantial thickness.

18. A foot attachableto abrading, bufling,

and polishing machines or the like, including an attaching elementhaving a body portion with attaching projections; and a block of inherently adhesive material ofsubstantial thickness molded about the element.

19. A foot attachable to abrading, bufling, and polishing machines or the like, including an attaching element having a body portion with attaching projections; and a block of inherently adhesive materialof substantial thickness molded about the element the pro- .jections protruding from'the molded block to permit attachment.

In testimony whereof I aflix my-signature.

ELTON E. 'HUMMERICI-I. 

